Estimation of the optimum phase for distributed scatterers by Modified Alternating Projection algorithm

摘要

To overcome the shortage of Persistent ScatterersrnInterferometry (PSI) that there is less PS in non-urban areas,rnthe distributed scatters (DS) was proposed. The spatialrndensity of measurement points is extremely enhanced byrnmean of jointly processing PS and DS. In order to jointlyrnprocess PS with DS, the phase for DS must be optimized.rnPrevious studies, namely, SqueeSARTM [1], have shownrntheir advantages in improving the estimation accuracy ofrnphase values by all possible interferograms. However, thisrnmethod does not fully considered the bias of coherencernmatrix. Moreover, it is much computationally intensive. Inrnthis paper, we present an efficient algorithm for computingrnthe exact maximum likelihood estimator of the phase valuesrnfor distributed targets.